Avalanche accident on the Dugway

Location Name: 
Mt. Rose Highway
Region: 
Mount Rose Area
Date and time of avalanche (best estimate if unknown): 
Sat, 03/09/2013 - 12:30


Red Flags: 
Recent avalanche activity
Whumphing noises, shooting cracks, or collapsing
Recent loading by new snow, wind, or rain
Obvious avalanche path
Terrain Trap

Observation made by: Professional Observer
Avalanche Observations
Avalanche Type: 
dry,slab,
Slope: 
45degrees
Trigger type: 
Snowboarder
Crown Height: 
1 ft
Aspect: 
North
Weak Layer: 
Old Snow
Avalanche Width: 
40ft.
Terrain: 
Below Treeline
Elevation: 
8 750ft.
Bed Surface: 
Old Snow
Avalanche Length: 
100ft.
Number of similar avalanches: 
2
Number of people caught: 
1
More detailed information about the avalanche: 

Avalanche occured today on the Mt. Rose  Highway Corridor in an area known as the Dugway. The avalanche was about 60 feet below a GasX unit in the GasX slide path. This path and the others along this section of road have been regularly controlled with the GasX exploders throughout the season and as a result the snowpack in these paths is shallower and has some differenent characteristics than other non-controled areas. The GasX had not been shot prior to this  avalanche or at all in the recent storm cycle.  The avalanche was reported to the Sierra Avalanche Center by a motorist on the Mt. Rose HIghway who witnessed the event and saw other motorists free the snowboarder from the avalanche. The victim left the site before any rescue personel arrived, it  is unknown at this time wheteher this was a full or partial burial. A motorist also  called Washoe County Sheriff, I was dispatched to the site with two other patrollers and my dog. When we arrived we were informed that a beacon search had been done and nothing turned up. There was an obvious large hole about 5 feet uphill from the toe about 3 feet deep where the victim was freed from. I ran the dog through the site andfound no other reason to believe anyone was buried we also had three patrollers probing likely areas. We performed control work on adjacent slopes using hand charges and had results similiar to the snowboarder triggered avalanche on one adjacent slope. I did a quick crown profile as well.

Snowpit or crown profile photo or graph: 
Avalanche Photos: 
Weather Observations
Blowing Snow: 
No
Cloud Cover: 
Clear
Air temperature: 
Below Freezing
Wind Speed: 
Light
Precipitation: 
None
Air temperature trend: 
Cooling
Wind Direction: 
Southwest
Accumulation rate: 
None
More detailed information about the weather: